It is difficult to translate it directly from Japanese to English.
If you translate it, it nearly means ‘obsession’. Have you ever been obsessed with someone or something? How does it feel like?
執(syuu)= It means to obsess over something.
念(nen)= It has a lot of meanings in Japan especially when used alone. However, in this context, it means a ‘great desire to make things happen sooner’.
As a whole,
執念(syuu-nen) = This phrase literally expresses ‘strong obsession’. It can be positive or negative depending on what you’re hooked on. If you’re obsessed with self-improvement despite setbacks, I’d say it’s a good kind of obsession.
If you are interested in these Kanji, you may simply copy them from this website and use them as you please. Make them yours!